Needle holder instruments have long been available in the art, and used by surgeons and surgical team members. Such instruments facilitate surgical suture needle passage through tissue followed by suture knot tying and subsequent suture cutting required for ligating or tagging structures, closing surgical incisions and traumatic wounds, and any other surgical use requiring suturing. Typically a standard needle holder or driver and separate suture scissors have been necessary, requiring the user to switch between instruments (needle holder and scissors), or employ the use of an additional person or assistant to perform the act of suture cutting with scissors between the placement of individual sutures by the surgeon. Many attempts have been made to devise a dual-function instrument to reduce man-hours of work in the surgical field, reduce surgical suture time and, consequently, overall surgical case time.
Several of the known devices operate by closing the handles both to grip the needle and to cut the sutures. This requires careful timing and placement of the suture to be sure it is not cut too early in the operational process, and that the nose of the jaws does not damage the surrounding tissue. Other known devices include a third element as part of the instrument to function for cutting purposes. Some such dual function devices are relatively complex and difficult to maneuver in the tight confines of a surgical procedure. Some commercially available instruments suffer from one or both of the two major deficiencies inferred above. One such deficiency is the potential for inadvertent premature cutting of the suture during the act of suturing. Another is the potential to damage tissue with the distal needle holder tip of the instrument when cutting the suture in the more proximal scissors structure of the device.
The problem of inadvertent premature cutting of the suture has been recognized and U.S. Pat. No. 4,271,838 discloses a modified needle holder having a modified tip with a protected cutting mechanism and a slot in which to capture and cut the suture. This structure moves the cutting mechanism toward the tip of the instrument, improving accuracy, but still incompletely prevents the most distal needle holder tip from damaging tissue when the instrument is closed during the suture cutting process. Additionally, the cutting blade may be prone to catching tissue or suture material during the act of suturing. It is significant that the cutting mechanism of the instrument shown in the '838 patent is actuated by closing the handles and jaws of the instrument, as is true of most pivoted instruments.